code: def test_pushpull():
      ctx = (
          mx.gpu(kv.local_rank)
          if mx.device.num_gpus() > 0
          else mx.cpu(kv.local_rank)
      )
      scale = kv.rank + 1
      tensor = mx.nd.ones(shape, ctx) * scale
      kv.pushpull("3", tensor)
  
      expected = (kv.num_workers + 1) * kv.num_workers / 2
      check_diff_to_scalar(tensor, expected)
      print("worker " + str(kv.local_rank) + " passed test_pushpull")
  
file_path: mxnet/tests/nightly/dist_device_sync_kvstore_horovod.py
imports: import sys
  import mxnet
  import numpy
  import numpy.random
  import time
  import argparse
label_desc: Use image node_id 2 for calling a global function with example usage: test_pushpull() without return types